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51.
The purpose of the review is to consider pathomechanisms of Sj?gren's syndrome (SS), which could explain the female dominance (9:1), the most common age of onset (40-50 years) and targeting of the exocrine glands. Estrogens seem to specifically protect secretory glandular acinar cells against apoptosis whereas lack of estrogens during menopause and climacterium specifically leads to increased apoptosis of the exocrine secretory cells. Male gonads produce testosterone and convert it in exocrine glands to dihydrotesterosterone (DHT), which is anti-apoptotic and protects against acinar cell apoptosis. Estrogen-deficient women need to produce dehydroepiandrosterone (DHEA) in the adrenal glands and convert it to DHT in exocrine glands in a complex and branching reaction network in which individual enzymatic reactions are catalyzed in forward and backward directions by a myriad of different isoforms of steroidogenic enzymes. Tailoring DHT in peripheral tissues is much more complex and vulnerable in women than in men. In SS the intracrine steroidogenic enzyme machinery is deranged. These endo-/intracrine changes impair acinar remodeling due to impaired integrin α1β1 and integrin α2β1 expression so that the intercalated duct progenitor cells are unable to migrate to the acinar space, to differentiate to secretory acinar cells upon contact with laminin-111 and laminin-211 specifically found in the acinar basement membrane. The disarranged endo-/intracrine estrogen/androgen balance induces acinar cells to release microparticles and apoptotic bodies and to undergo apoptotis and/or anoikis. Membrane particles contain potential autoantigens recognized by T- (TCRs) and B-cell receptors (BCRs) and danger-associated molecular patterns (DAMPs) recognized by Toll-like receptors (TLRs). In membrane particles (or carrier-complexes) antigen/adjuvant complexes could stimulate professional antigen capturing, processing and presenting cells, which can initiate auto-inflammatory and autoimmune cascades, break the self-tolerance and finally lead to SS.  相似文献   
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It has been shown that the psychosocial environment perceived by school staff is associated with children’s academic performance and wellbeing. In this study we examined the associations between organizational justice (procedural and relational justice) as reported by school staff and pupils’ perceptions of their school environment, health problems, academic performance, and absenteeism. We combined data from two surveys: for the staff (the Finnish Public Sector Study, n = 1946) and pupils (the Finnish school health promotion survey, n = 11,781 boys and 12,842 girls) of 136 secondary schools, collected during 2004–2005. Multilevel cumulative logistic regression analyses showed that after adjustment for potential individual and school-level confounding factors, low procedural justice was associated with pupils’ dissatisfaction with school-going. Low relational justice was associated with a 1.30 times higher risk of poor academic performance, 1.15 times higher risk of psychosomatic symptoms and 1.13 times higher risk of depressive symptoms among pupils. Both organizational justice components were associated with truancy. We concluded that staff perceptions of organizational justice at school are associated with pupils’ reports of their psychosocial school environment, health, performance, and absenteeism due to truancy. Improving managerial and decision making procedures among school personnel may be an important factor for protecting pupils’ academic performance and wellbeing.  相似文献   
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This article examines the self‐rated health, symptoms and health behaviour of upper secondary vocational students in Finland. The data consist of the responses of first‐ and second‐year vocational students (n = 34 554) to the 2013 School Health Promotion Survey. The data were analysed statistically and processed separately for girls and boys. Associations between self‐rated health, symptoms and health behaviour and fields of study were examined by cross‐tabulation. Statistical significance was measured using the chi‐squared test. Self‐rated health, symptoms and health behaviour were found to have a statistically significant association with field of study (p < 0.001). Vocational students in different fields had different experiences of health, different symptoms and different health behaviours. The results complement existing evidence about disparities in well‐being among young people in the context of education.  相似文献   
56.

Objectives

To characterize the clinical utility of Sport Concussion Assessment Tool 3 (SCAT3) baseline and normative reference values for the assessment of acute concussion; and to identify the sensitivity of each SCAT3 subcomponent to the acute effects of concussion.

Design

Prospective cohort.

Methods

The day-of-concussion SCAT3 results (n = 27) of professional male ice hockey players (mean age = 27, SD = 4) were compared to athlete’s individual baseline and to the league’s normative reference values. Normative cutoffs corresponding to 10th percentile and natural distribution change cutoffs corresponding to 90th percentile cumulative frequency were considered uncommon.

Results

The percentages of the players with uncommon day-of-injury performance, when post-injury scores were compared to individual baseline versus (vs.) normative values, were as follows: symptoms: 96% vs. 100% (post-injury score: M = 12, Md = 12, SD = 4; severity M = 26, Md = 23, SD = 13); Standardized Assessment of Concussion (SAC): 33% vs. 27% (post-injury M = 25, Md = 26, SD = 3); modified-BESS (M-BESS): 46% vs. 46% (post-injury M = 7, Md = 5, SD = 7); Tandem Gait: 18% vs. 31% (post-injury M = 11, Md = 12, SD = 4); coordination: both 8%. The number and severity of post-injury symptoms were significantly greater, with extremely large effect sizes (Cohen’s d = 2.44–3.92), than normative values and individual baseline scores. The post-injury SAC score was significantly lower relative to both baseline (d = 0.68) and normative values (d = 0.88). The post-injury M-BESS performance was significantly worse when compared to both individual baseline (d = 1.06) and league normative values (d = 1.46). No significant day-of-injury Tandem Gait deficits were observed using either comparison method.

Conclusions

SCAT3 league normative values were as sensitive as individual baseline scores during day-of-injury assessments. Symptoms were the most sensitive post-concussion component of the SCAT3.  相似文献   
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Intravascular ultrasound is widely used to guide coronary stent implantation. The key quantitative criterion for successful implantation is the demonstration of adequate expansion of the stented lumen relative to that of the adjacent reference vessel segments. In this study we aimed to establish the reproducibility of intravascular ultrasound measurements of the reference segments in lesions undergoing coronary stenting. Measurements of the reference segment lumen dimensions were made in a blinded fashion by two experienced observers, and reproducibility was assessed by calculating the mean difference and standard deviation of the paired measurements. The unselected intraobserver random variability of the mean reference lumen area measured 0.8 mm2. The interobserver random variability was 0.94 mm2. The intraobserver and interobserver variability of minimum lumen area within the stent was smaller, measuring 0.30 mm2 and 0.52 mm2, respectively. There was 91% intraobserver agreement, and 75% interobserver agreement, in identifying adequate stent expansion as defined by a stent-to-mean reference lumen area ratio of >0.8. The potentially significant level of variability inherent in selecting and measuring the reference segments, and its impact on clinical decision-making, should be remembered when this method of assessing the acute quantitative outcome of stent implantation is applied. Cathet Cardiovasc Diagn 40:1–7, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
59.
Domestic wood combustion and traffic are the two most significant primary fine particulate matter (PM2.5) emission source categories in Finland. We estimated emission–exposure relationships for primary PM2.5 emissions from these source categories using intake fractions (iF), which describes the fraction of an emission that is ultimately inhaled by a target population. The iFs were calculated for four different emission source subcategories in Finland in 2000: (1) domestic wood combustion in residential buildings, (2) domestic wood combustion in recreational buildings, (3) traffic exhaust and wear emissions, and (4) traffic resuspension emissions. The iFs were estimated for both total population and for subpopulations with different gender, age, and educational status. Primary PM2.5 emissions were based on the Finnish Regional Emission Scenario model and the dispersion of particles was calculated using the Urban Dispersion Modeling system of Finnish Meteorological Institute. Both emissions and dispersion were estimated on a 1 km spatial resolution. The iFs for primary PM2.5 emissions from (1) residential and (2) recreational buildings were 3.4 and 0.6 per million, respectively. The corresponding iF for (3) traffic exhaust and wear and (4) traffic resuspension emissions were 9.7 and 9.5 per million, respectively. The differences in population-weighted outdoor concentrations were significant between subpopulations with different educational status so that people with higher education were exposed more to traffic-related PM2.5.  相似文献   
60.
OBJECTIVE: To evaluate and compare interobserver variation in interpretation of intrapartum cardiotocograms. SUBJECTS: Fifteen senior (experience >4 years) and 16 junior (experience < or =4 years) obstetricians from 10 delivery units. DESIGN: Thirty-one obstetricians interpreted intrapartum cardiotocographic (CTG) readings from 22 parturients. METHODS: Inter-observer agreement in CTG interpretation and decision-making was assessed via proportions of agreement (Pa), with 95% confidence intervals (CI). MAIN OUTCOME MEASURES: The level of inter-observer agreement was analyzed by calculating Pa values for CTG baseline, variability, early, variable and late decelerations, uterine tonus, power of contractions, hypertonus and clinical decision. RESULTS: In assessments of normal cases the Pa were acceptable or good (0.63-0.82) as regards all CTG interpretation elements except for the power of contractions (0.24), but in assessments of abnormal cases the Pa values were lower (0.18-0.60). As regards clinical decisions, a higher Pa was found in cases without recommendation for intervention (0.63, 95% CI 0.62-0.64) than in cases with such recommendation (0.55, 95% CI 0.54-0.56). The Pa in the abnormal cases was better among senior than among junior obstetricians. CONCLUSIONS: Inter-observer variation in interpretation of abnormal CTG readings and recommendations for intervention is relatively wide. To improve reliability, uniform classification and standardized training in CTG interpretation are needed, as well as increased use of computerized CTG.  相似文献   
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